Planning and control of indirect simultaneous positioning operation for deformable objects

A control method for positioning operations of deformable objects is presented. In many manipulative operations of deformable objects, it is required to guide multiple points on on object simultaneously. Moreover, the points often cannot be manipulated directly. A model of the manipulated deformable object is essential to perform these operations. It is, however, difficult to build a precise model of a deformable object. Thus, we need a new control scheme that allows us to perform the operations successfully despite of discrepancy between a manipulated deformable object and its model. We introduce a coarse model of a deformable object and develop a control law for its positioning operation. First, we propose a mathematical model of deformable objects for their positioning operations. Second, indirect simultaneous positioning operations of deformable objects is formulated. Then, we propose an iterative control method to realize a given positioning operation. The validity of the proposed method and the effect of model errors on the operation are examined through experiments using textile fabrics. Experimental results show that coarse model of deformable objects is effective for their positioning operations. Finally, we discuss the locations of robotic fingers, which apply forces to a manipulated object